Limits...
Drug Development in Conformational Diseases: A Novel Family of Chemical Chaperones that Bind and Stabilise Several Polymorphic Amyloid Structures.

Sablón-Carrazana M, Fernández I, Bencomo A, Lara-Martínez R, Rivera-Marrero S, Domínguez G, Pérez-Perera R, Jiménez-García LF, Altamirano-Bustamante NF, Diaz-Delgado M, Vedrenne F, Rivillas-Acevedo L, Pasten-Hidalgo K, Segura-Valdez Mde L, Islas-Andrade S, Garrido-Magaña E, Perera-Pintado A, Prats-Capote A, Rodríguez-Tanty C, Altamirano-Bustamante MM - PLoS ONE (2015)

Bottom Line: It has devastating effects on the sufferers as well as a tremendous economic impact on families and the health system.Furthermore, all the chaperones are able to protect and recondition the cerebellar granule cells (CGC) from the cytotoxicity produced by the hIAPP20-29 fragment or by a low potassium medium, regardless of their capacity for accelerating or inhibiting in vitro formation of fibers.In vivo animal experiments are required to study the impact of chemical chaperones in cognitive and metabolic syndromes.

View Article: PubMed Central - PubMed

Affiliation: Dpto. Neurodiagnóstico, Centro de Neurociencias de Cuba, Cubanacán, Playa, La Habana, Cuba; Unidad de Investigación Médica en Enfermedades Metabólicas, Hospital de Cardiología, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, México D.F., México.

ABSTRACT
The increasing prevalence of conformational diseases, including Alzheimer's disease, type 2 Diabetes Mellitus and Cancer, poses a global challenge at many different levels. It has devastating effects on the sufferers as well as a tremendous economic impact on families and the health system. In this work, we apply a cross-functional approach that combines ideas, concepts and technologies from several disciplines in order to study, in silico and in vitro, the role of a novel chemical chaperones family (NCHCHF) in processes of protein aggregation in conformational diseases. Given that Serum Albumin (SA) is the most abundant protein in the blood of mammals, and Bovine Serum Albumin (BSA) is an off-the-shelf protein available in most labs around the world, we compared the ligandability of BSA:NCHCHF with the interaction sites in the Human Islet Amyloid Polypeptide (hIAPP):NCHCHF, and in the amyloid pharmacophore fragments (Aβ17-42 and Aβ16-21):NCHCHF. We posit that the merging of this interaction sites is a meta-structure of pharmacophore which allows the development of chaperones that can prevent protein aggregation at various states from: stabilizing the native state to destabilizing oligomeric state and protofilament. Furthermore to stabilize fibrillar structures, thus decreasing the amount of toxic oligomers in solution, as is the case with the NCHCHF. The paper demonstrates how a set of NCHCHF can be used for studying and potentially treating the various physiopathological stages of a conformational disease. For instance, when dealing with an acute phase of cytotoxicity, what is needed is the recruitment of cytotoxic oligomers, thus chaperone F, which accelerates fiber formation, would be very useful; whereas in a chronic stage it is better to have chaperones A, B, C, and D, which stabilize the native and fibril structures halting self-catalysis and the creation of cytotoxic oligomers as a consequence of fiber formation. Furthermore, all the chaperones are able to protect and recondition the cerebellar granule cells (CGC) from the cytotoxicity produced by the hIAPP20-29 fragment or by a low potassium medium, regardless of their capacity for accelerating or inhibiting in vitro formation of fibers. In vivo animal experiments are required to study the impact of chemical chaperones in cognitive and metabolic syndromes.

No MeSH data available.


Related in: MedlinePlus

A. ThT fluorescence kinetics during amyloid fibrillation of BSA.Experiments were carried out at 65°C in glycine buffer (pH = 3; 0.05M, NaCl 100 mM), in presence or absence of the selected chaperones at molar relation 1:1 of BSA: Chap. (ThT: 24 μM). Time dependent changes in ThT intensity was fitted by exponential function (solid line). In all cases, the adjusted R-square values were greater than 0.9. The experiments were carried out in triplicate. The control BSA alone (black square) and BSA plus DMSO (white triangles). All the chaperones (empty squares) were compared with BSA plus DMSO (black squares). B: Normalized maximum values of the ThT fluorescence intensity of BSA fibrilations in presence or absence of chaperones (A, B, C, D, E, F and G).
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4556714&req=5

pone.0135292.g006: A. ThT fluorescence kinetics during amyloid fibrillation of BSA.Experiments were carried out at 65°C in glycine buffer (pH = 3; 0.05M, NaCl 100 mM), in presence or absence of the selected chaperones at molar relation 1:1 of BSA: Chap. (ThT: 24 μM). Time dependent changes in ThT intensity was fitted by exponential function (solid line). In all cases, the adjusted R-square values were greater than 0.9. The experiments were carried out in triplicate. The control BSA alone (black square) and BSA plus DMSO (white triangles). All the chaperones (empty squares) were compared with BSA plus DMSO (black squares). B: Normalized maximum values of the ThT fluorescence intensity of BSA fibrilations in presence or absence of chaperones (A, B, C, D, E, F and G).

Mentions: The Thioflavin T (ThT) fluorescence is widely used to study the kinetics of amyloid fibril formation in different proteins [13]. According to the studies consulted, the fibril formation mechanism of BSA is distinguished from others on account of its mechanism of aggregation, which is composed of two states: a logarithmic phase of rapid growth, corresponding to fibril elongation, and a plateau phase of stationary growth, during which there may be continuing morphological changes that can be fitted into a single exponential decay without any lag phase. The ThT fluorescent assay was used to monitor the fibril formation of BSA in the presence or absence of the novel family of chemical chaperones. NCHCHF were added to the ThT assay, in a molar ratio of 1:1 BSA: chaperone. Fig 6A shows ex situ measurements of ThT emission intensity with and without chaperones. Triplicate aggregation kinetics were developed at different times at 65°C. The samples were cooled in order to stop the aggregation process as described by Vetry et al. [9] BSA aggregation was significantly inhibited with increasing doses of chemical chaperones A, C, D and E, with A IC50 of 6.34 μmol/L, 9.21 μmol/L, 6.37 μmol/L and 5.38 μmol/L, respectively. Although chaperone F (40 μmol/L) showed the highest IC50 value, this compound delayed the BSA aggregation and also diminished the total amount of fiber.


Drug Development in Conformational Diseases: A Novel Family of Chemical Chaperones that Bind and Stabilise Several Polymorphic Amyloid Structures.

Sablón-Carrazana M, Fernández I, Bencomo A, Lara-Martínez R, Rivera-Marrero S, Domínguez G, Pérez-Perera R, Jiménez-García LF, Altamirano-Bustamante NF, Diaz-Delgado M, Vedrenne F, Rivillas-Acevedo L, Pasten-Hidalgo K, Segura-Valdez Mde L, Islas-Andrade S, Garrido-Magaña E, Perera-Pintado A, Prats-Capote A, Rodríguez-Tanty C, Altamirano-Bustamante MM - PLoS ONE (2015)

A. ThT fluorescence kinetics during amyloid fibrillation of BSA.Experiments were carried out at 65°C in glycine buffer (pH = 3; 0.05M, NaCl 100 mM), in presence or absence of the selected chaperones at molar relation 1:1 of BSA: Chap. (ThT: 24 μM). Time dependent changes in ThT intensity was fitted by exponential function (solid line). In all cases, the adjusted R-square values were greater than 0.9. The experiments were carried out in triplicate. The control BSA alone (black square) and BSA plus DMSO (white triangles). All the chaperones (empty squares) were compared with BSA plus DMSO (black squares). B: Normalized maximum values of the ThT fluorescence intensity of BSA fibrilations in presence or absence of chaperones (A, B, C, D, E, F and G).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4556714&req=5

pone.0135292.g006: A. ThT fluorescence kinetics during amyloid fibrillation of BSA.Experiments were carried out at 65°C in glycine buffer (pH = 3; 0.05M, NaCl 100 mM), in presence or absence of the selected chaperones at molar relation 1:1 of BSA: Chap. (ThT: 24 μM). Time dependent changes in ThT intensity was fitted by exponential function (solid line). In all cases, the adjusted R-square values were greater than 0.9. The experiments were carried out in triplicate. The control BSA alone (black square) and BSA plus DMSO (white triangles). All the chaperones (empty squares) were compared with BSA plus DMSO (black squares). B: Normalized maximum values of the ThT fluorescence intensity of BSA fibrilations in presence or absence of chaperones (A, B, C, D, E, F and G).
Mentions: The Thioflavin T (ThT) fluorescence is widely used to study the kinetics of amyloid fibril formation in different proteins [13]. According to the studies consulted, the fibril formation mechanism of BSA is distinguished from others on account of its mechanism of aggregation, which is composed of two states: a logarithmic phase of rapid growth, corresponding to fibril elongation, and a plateau phase of stationary growth, during which there may be continuing morphological changes that can be fitted into a single exponential decay without any lag phase. The ThT fluorescent assay was used to monitor the fibril formation of BSA in the presence or absence of the novel family of chemical chaperones. NCHCHF were added to the ThT assay, in a molar ratio of 1:1 BSA: chaperone. Fig 6A shows ex situ measurements of ThT emission intensity with and without chaperones. Triplicate aggregation kinetics were developed at different times at 65°C. The samples were cooled in order to stop the aggregation process as described by Vetry et al. [9] BSA aggregation was significantly inhibited with increasing doses of chemical chaperones A, C, D and E, with A IC50 of 6.34 μmol/L, 9.21 μmol/L, 6.37 μmol/L and 5.38 μmol/L, respectively. Although chaperone F (40 μmol/L) showed the highest IC50 value, this compound delayed the BSA aggregation and also diminished the total amount of fiber.

Bottom Line: It has devastating effects on the sufferers as well as a tremendous economic impact on families and the health system.Furthermore, all the chaperones are able to protect and recondition the cerebellar granule cells (CGC) from the cytotoxicity produced by the hIAPP20-29 fragment or by a low potassium medium, regardless of their capacity for accelerating or inhibiting in vitro formation of fibers.In vivo animal experiments are required to study the impact of chemical chaperones in cognitive and metabolic syndromes.

View Article: PubMed Central - PubMed

Affiliation: Dpto. Neurodiagnóstico, Centro de Neurociencias de Cuba, Cubanacán, Playa, La Habana, Cuba; Unidad de Investigación Médica en Enfermedades Metabólicas, Hospital de Cardiología, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, México D.F., México.

ABSTRACT
The increasing prevalence of conformational diseases, including Alzheimer's disease, type 2 Diabetes Mellitus and Cancer, poses a global challenge at many different levels. It has devastating effects on the sufferers as well as a tremendous economic impact on families and the health system. In this work, we apply a cross-functional approach that combines ideas, concepts and technologies from several disciplines in order to study, in silico and in vitro, the role of a novel chemical chaperones family (NCHCHF) in processes of protein aggregation in conformational diseases. Given that Serum Albumin (SA) is the most abundant protein in the blood of mammals, and Bovine Serum Albumin (BSA) is an off-the-shelf protein available in most labs around the world, we compared the ligandability of BSA:NCHCHF with the interaction sites in the Human Islet Amyloid Polypeptide (hIAPP):NCHCHF, and in the amyloid pharmacophore fragments (Aβ17-42 and Aβ16-21):NCHCHF. We posit that the merging of this interaction sites is a meta-structure of pharmacophore which allows the development of chaperones that can prevent protein aggregation at various states from: stabilizing the native state to destabilizing oligomeric state and protofilament. Furthermore to stabilize fibrillar structures, thus decreasing the amount of toxic oligomers in solution, as is the case with the NCHCHF. The paper demonstrates how a set of NCHCHF can be used for studying and potentially treating the various physiopathological stages of a conformational disease. For instance, when dealing with an acute phase of cytotoxicity, what is needed is the recruitment of cytotoxic oligomers, thus chaperone F, which accelerates fiber formation, would be very useful; whereas in a chronic stage it is better to have chaperones A, B, C, and D, which stabilize the native and fibril structures halting self-catalysis and the creation of cytotoxic oligomers as a consequence of fiber formation. Furthermore, all the chaperones are able to protect and recondition the cerebellar granule cells (CGC) from the cytotoxicity produced by the hIAPP20-29 fragment or by a low potassium medium, regardless of their capacity for accelerating or inhibiting in vitro formation of fibers. In vivo animal experiments are required to study the impact of chemical chaperones in cognitive and metabolic syndromes.

No MeSH data available.


Related in: MedlinePlus